# S-Species-Stimulated Deep Reconstruction of Ultra-Homogeneous CuS Nanosheets for Efficient HMF Electrooxidation

## TL;DR

This paper introduces a new method to create efficient copper sulfide nanosheets for converting biomass into valuable chemicals.

## Contribution

A coordination-pyrolysis strategy is proposed to fabricate CuS nanosheets with enhanced HMF oxidation performance.

## Key findings

- The optimized CuS@NC achieved a current density of 335 mA cm−2 at 1.50 V.
- The method shows a 628% improvement over the control catalyst.
- S species trigger deep reconstruction and promote bond cleavage in HMF.

## Abstract

Efficient utilization of renewable biomass resources is one of the feasible approaches to address the massive consumption of fossil fuels accompanying severe resource crises and environmental pollution. Currently, 2,5-furandicarboxylic acid derived from the oxidation of biomass-based 5-hydroxymethylfurfural (HMF) is a valuable chemical as the alternative to the fossil resource-derived terephthalic acid. However, the development of high-performance and low-cost Cu-based electrocatalysts for the efficient HMF oxidation reaction (HMFOR) remains an enormous challenge. Guided by our theoretical prediction, we proposed a coordination-pyrolysis strategy to fabricate highly dispersed copper sulfide (CuS) nanosheets supported on N-doped porous carbon precatalyst (CuS@NC). The covalent S species trigger the deep reconstruction of CuS nanosheets, and the in situ generated SO42− not only promotes the formation of Cu2+δ species but also facilitates the cleavage of α–C–H and –O–H bonds in HMF. The optimized CuS@NC achieved a high current density of 335 mA cm−2 at 1.50 V vs. reversible hydrogen electrode, representing a remarkable 628% enhancement over the control catalyst. This study integrates theoretical predictions with experimental investigations to systematically elucidate how S species promote the deep reconstruction of CuS nanosheets to enhance the HMFOR performance and proposes a scalable strategy for preparing ultra-uniform transition metal sulfide precatalysts.